HYPERICUM - ST. JOHN'S - WORT

Author: Kelly Kurz-Blalock


Permanent E-Mail Address:
kblalock@arches.uga.edu
Class E-Mail Address:
350kurzblalock@dial.pick.uga.edu



Courtesy,University of Georgia Herbarium

Table of Contents


Higher Taxon:

Family:

Hypericaceae

Description:

"A peculiarity of the St. John's-Wort Family is that the leaves contain glands, containing oil and sometimes a pigment, which appear as translucent spots when held against a source of light, or as black dots on the surface" (Ricket.,1966)."Hypericum are found as either herbs or shrubs, sometimes small trees in tropical regions, with opposite or rarely verticillate simple entire or rarely glandular-ciliate or dentate leaves, no stipules, resinous juice and terminal or axillary, solitary or cymose-paniculate flowers"(Abrams.,1951). Heywood, describes the flowers of Hypericum as, "bisexual or unisexual and borne on separate plants, and single or grouped in a cymose or thyrsoid inflorescence"(Heywood.,1978). Eisendrath, describes the flowers as, "regular, hypogynous, usually perfect, 4-5 merous; usually yellow; 3-5 stigmas; many stamens, often united in groups"(Eisendrath.,1978).

Species List:

The Species List lists some scientific names and known common names for Hypericum. NOTE, because there are over 300 known species I'm only listing those species found in The Manual of Vascular Flora of the Carolinas
. Link here for two specific species,
H.hypericoides and H.mutilum.

Identification Guide: The following key shows some characteristics of different species within the genus Hypericum as presented in Radford, Ahles and Bell's Manual of the Vascular Flora of the Carolinas The descriptions represent those species found in most of the southeastern states.

"I. Petals 4; sepals 2 or 4.

A: Styles 2; inner sepals minute or obsolete.

1. Pedicel reflexed in fruit; bractlets at base or pedicel........H.suffruticosum

2. Pedicel erect in fruit; bractlets near base of calyx.

a. Plant erect........H.hypericoides

b. Plant decumbent........H.Stragalum

B: Styles 3 or 4; sepals subequal........H.stans

II. Petals 5; sepals 5
Petals yellow; hypogynous glands absent.

A: Plant herbaceous

1. Leaves spreading, usually 3 or more nerved.

a. Styles separate; stigmas capitate.
*styles 1mm or less long; stamens 12 or fewer ovary and capsule without prominent oil vesicles.

a. Leaves less than 3mm wide, 1 to 3 nerved........H.canadense

2. Leaves more than 3mm wide, 5 to 7 nerved.

a. Sepals lanceolate; capsule conic........H.gymnanthum

b. Sepals narrowly elliptic; capsule oblong to elliptic........H.mutilum"

(Radford et al., 1968).


General Information:

Hypericum is an ancient Greek name of a plant derived from the word heather (ereike) and the prefix beneath (hypo)(Bailey.,1928). The leaves of Hypericum have been used in drugs and homeopathy. "Hypericum is often prescribes for bodily induries, among other conditions; but it is selected for the soothing effect it is said to have on injured nerves rather than for any traditional reason. The entire plant is harvested for homeopathic use in summer, when its yellow flowers are in full bloom. The major target ailments are: backaches, bites and stings from animals and insects, and cuts and wounds to nerve rich parts of the body"(www.onhealth.com/harts/chest/drugs/htm/hyperic.htm) For more information regarding St. John's-Wort (Hypericum) vs. prozac as a way of treating depression, go to (www.NIMH.gov)

References:

  1. Abrams, L. 1951. Illustrated Flora of the Pacific States. Stanford University Press. Stanford, Ca

  2. Bailey, L.H. 1928. The Standard Cyclopedia of Horticulture. The Macmillan Company. New York, NY.

  3. Duncan, W.H. M.B. 1987. Seaside Plants of the Gulf and Atlantic Coasts. Smithsonian Institution Press. Washington D.C.

  4. Eisendrath, E.R. 1978. Missouri Wildflowers of the St. Louis Area. Missouri Botanical Garden. St. Louis, Missouri

  5. Fernald, M.L. 1950. Gray's Manual of Botany. American Book Company. New York, NY.

  6. Gleason, H.A. 1952. Illustrated Flora of the Northeastern united States and adfacent Canada. Lancaster Press, Inc. Lancaster, Pa

  7. Godfrey, R.K. & J.W. Wooten. 1981. Aquatic and Wetland Plants of Southeastern United States. University of Georgia Press. Athens, Ga

  8. Heywood, V.H. 1978. Flowering Plants of the world. Oxford University Press. Oxford, England

  9. Jackson,B.D. 1895. Index Kewensis Volume 1. Clarendon Press. Oxford, England

  10. Jones, S.B. & N.C. Coile. 1988 Distribution of the Vascular Flora of Georgia. Dept. of Botany, University of Georgia. Athens, Ga.

  11. Radford, A.E., H.E. Ahles & C.R. Bell. 1968 Manual of Vascular Flora of the Carolinas. University of North Carolina Press. Chapel Hill, NC

  12. Ricket,H.W. 1966. Wild Flowers of the United States (The Southeastern States). McGraw Hill Book Company. New York, NY.

  13. Vines, R.A. 1960. Trees, Shrubs, and Woody Vines of the Southwest. University of Texas Press. Austin, Tx.

  14. www.onhealth.com/harts/chest/drugs/htm/hyperic.htm

  15. www.NIMH.gov

Back to Table of Contents